ABSTRACT
Background: Evolution of individualized radiosurgical therapeutic methods for brain metastasis as an ominous prognostic finding may encourage a more extensive application of neuroimaging in patients with extracerebral cancer. The aim of the present study was to investigate the added value of brain-included 18 F FDG PET/CT acquisition protocol based on primary cancer type and clinical indication
Materials and Methods: A retrospective review was performed on 3945 18 F FDG PET/CT reports of patients with extra-cerebral cancer underwent brain-included PET/CT study. Cerebral lesions suggestive of brain metastasis were subsequently verified by MRI, MRI+MRS, surgical pathology and a 1-year clinical formal follow up. The detection rate of new brain metastasis and related impact on disease status were then investigated in each cancer type based on clinical indication
Results: Of a total 3933 eligible patients, 44 [1.12%] were finally verified to have new cerebral metastasis. The most common primary sources were lung cancer [19/385, 4.93%], cancer of unknown primary [CUP] [5/168, 2.97%] and breast cancer [8/468, 1.71%]. The most common clinical indications were initial staging [17/44, 43.1%] and restaging [19/44, 36.4%]. Change in disease status occurred in 12 out of 44 patients [27.3%], more frequently occurred in lung cancer [n=4], in all indications and breast [n=3] cancers at restaging [n=7, 43.8%]
Conclusion: PET/CT acquisition protocol study may be best optimized based on the type of primary cancer and timing of evaluation. Brain-included field of view may be recommended for lung cancer regardless the clinical indication, cancer of unknown primary and breast cancer at restaging
ABSTRACT
Background: Breast incidental lesion at 18 F FDG PET/CT are occasionally encountered in cancer patients, which may represent a second primary malignancy. The aim of the present study was to investigate the diagnostic performance of PET metabolic parameters to characterize breast incidentaloma
Materials and Methods: All the images of patients with cancers other than breast with breast incidental lesion underwent PET/CT scan at Masih Daneshvari Hospital between May 2012 and May 2016 were retrieved and reviewed. SUVmax, SUVmean, MTV and TLG in addition to associated morphologic features on CT and demographics were recorded and correlated with final diagnosis defined by histophatologic confirmation or an at least 1-year clinical formal follow up
Results: Of a total 58 from 51 patients [51/5029, 1.01%], 10 [19.60%] were histopathologically verified as second primary breast cancers. There was a statistically significant difference in SUVmax, SUVmean, MTV and TLG between benign and malignant group [1.64 vs. 5.32 [p=0.009], 1.34 vs. 3.69 [p=0.027], 0.96 vs. 2.62 [p=0.035], 1.54 vs 8.89 [p=0.006]. Using cut off 2, 1.35, 1.16 and 1.75, sensitivity and specificity of SUVmax, SUVmean, MTV and TLG were calculated as 77% and 62%, 92% and 66.5%, 77% and 75% 77% and 67%, respectively
Conclusion: Despite a significantly higher value in malignant breast incidental lesion, PET-derivative metabolic parameters provided only modest sensitivity and specificity and hence may not be considered as the sole criteria for risk stratification in this clinical setting